In spring 2002, researchers from the BBC television programme Frontline Scotland stumbled across what would become a very big story. They were looking into the mysterious death by shooting of James Collinson, a young army recruit from Perth, and they had already established that a strikingly similar death had occurred at the same Surrey barracks where Collinson died, just six months earlier. Then they made their big discovery: there had been not just two such deaths at the barracks, but four. Two young soldiers had died there in 1995, also by gunshot, and also in unexplained circumstances. So began the scandal of Deepcut. No great insight is required to see why that discovery made it a big story: two may be a coincidence, but four is something else.

Today, five years on, there is a general perception that the Deepcut scandal is over. Many people are under the impression that a proper inquiry has been conducted and that it found that the deaths were suicides. And besides, the affair has been crowded out by Iraq and Afghanistan. Though the Deepcut families have not given up, editors are now loath to commission articles about the affair; they believe, in rough terms, that it is now history. This represents a triumph for the Ministry of Defence, which in five years never rested in its efforts to kill a story that it would have preferred we had never known about.

Despite considerable difficulties, journalists did pretty well in pushing the story forward and unearthing new information, though it was always the bereaved families in the driving seat. But then I believe that in the end we were outmanoeuvred by the MoD, tricked if you like, into letting the matter drop. It was a simple trick and I am not sure what we could have done about it, but I think at least we should recognise that it happened.

After the scandal broke, for 15 months, the government was able to keep a lid on the Deepcut affair by simple means. The Surrey police, who had botched the investigations of the deaths the first time around (they later apologised), were conducting a re-investigation, and while that was going on ministers systematically refused to comment - the matter was in the hands of the police.

In September 2003 Surrey police completed their report, but did not publish it. All they issued was a four-page press release containing the headline statement that they had not found evidence to justify charging anyone.

It was a message superficially reassuring for the public but without any evidence on the record to support it. To this day the full report, reputed to be 2,500 pages long, is withheld from the public, and even the legal teams of the victims' families are not allowed to read it. The government used this as another smokescreen. In the Commons Tony Blair implied that everything possible had been done to unearth the truth. "There has been a very detailed police investigation of the deaths," he said, "with about 900 witnesses being interviewed and 1,500 statements taken over 15 months, and we are grateful to the chief constable of Surrey police for his report." (Readers with long memories might recall Richard Nixon's White House using very similar language to impart credibility to a Justice Department investigation which concluded that Watergate was a simple burglary.)

That the Deepcut affair did not run into the sand right there we owe, paradoxically, to the same Surrey police, who, after burying their report on the deaths, published an additional report in March 2004 which opened a new front: it addressed the Army's "duty of care" at the barracks in 1995-2002 and left little doubt that there had been grave failings. In the months that followed there was widespread outrage, articulated in and fed by revelatory television programmes and newspaper articles, as well as by public evidence to a Commons select committee investigation of Army duty of care.

Perhaps most shocking was the arrest in 2004 of a former Deepcut NCO, Leslie Skinner, who had exploited his authority to sexually abuse male trainee soldiers at the camp (he was later jailed). As the bereaved families drove pressure both within Parliament and outside, ministers looked for a way out.

So was created, in December 2004, the Deepcut Review, conducted by Nicholas Blake QC - and here we are approaching the point where journalism dropped the ball. The review was conducted behind closed doors over 15 months, though Blake met the families and persuaded them to co-operate (something they now regret). Then on March 29 last year Blake presented his report (the circumstances were carefully choreographed in that the families were not allowed to speak at the same press conference). It ran to 400 pages, with nearly 2,000 pages of appendices, but coverage of it was dominated by a single newsline: Blake concluded that, on the balance of probabilities, the soldiers had killed themselves. Other angles were covered in the press, in particular some further shocking information about bullying and neglect at Deepcut, but this finding of "probable suicide" was the key message.

Much else of vital importance in the Blake report was missed or obscured. Why did this happen? A simple, mechanical reason: there was just one window of opportunity for reporters to write about the report and they self-evidently did not have the time to digest it. Journalists could do little more than relay a soundbite, which happened also to be the one the MoD desperately wanted in the public domain.

Nothing unusual about that, you may say. Published reports are frequently long and journalists with deadlines are always under pressure to deal with them rapidly - Hutton, Scott and Macpherson were all reported in a hurry and in those three cases we got the message, didn't we? Perhaps, but Blake was different: it had not been a public inquiry. Reporters who follow an inquiry that has weighed evidence in months of open hearings are far better equipped to deal quickly with a long report than they were in the case of Blake. There were dozens of Hutton geeks who knew every twist of the case by the time that report came out, and as a result they were able to identify its weaknesses almost instantly. Not so with Blake; there are very few Deepcut geeks, and we are characterised by how little we know, rather than how much.

In my view, at the moment the 400-page outcome was unveiled, most people were still at square one in their understanding of the issues. There is a message here for campaigners: if at all possible, do not accept or cooperate with a behind-closed-doors investigation. There is also an important message for reporters and editors. Governments, when they think they can get away with it, will use this device again. They will spring a mass of information on us in the knowledge that we have no hope of processing it in time to meet that day's deadlines. We should be alert to this and should try to subvert it as we do all the other devices of spin.

I have in my notebook a remarkable quotation from Des James, the father of Cheryl James, killed by gunshot in Deepcut in 1995 at the age of 18. In exasperation at the news fix I have just described, he said to me last summer: "Was it suicide? Who the hell cares?" He wasn't being callous. What he meant was that when you realise the state of affairs in Deepcut, you see that the precise manner of the deaths is almost irrelevant. One way or another young people were bound to die in such a place, and the miracle is that there were not more deaths. Yet no one has been held to account.

That is the message that went astray because reporters and the public were outwitted.

· Brian Cathcart is professor of journalism at Kingston University.

· A longer version of this article appears in the British Journalism Review, Vol 18 No 1, available from SAGE Publications, 1 Oliver's Yard, 55 City Road, London EC1Y 1SP. Subscriptions: 020 7324 8703 or subscription@sagepub.co.uk